1. Field of the Invention
The present invention relates to an automatic correction method and device for automatically correcting an image displayed by a surface light source corresponding to a given set of image data and exposing the photosensitive material such as photographic printing paper, film, and the like to the image.
2. Discussion of the Related Art
Some conventional technologies have been known for displaying a certain image on a surface light source such as a CRT or a liquid crystal display and then exposing photosensitive material such as photographic printing paper or film to the light source with the image. When the photosensitive material is exposed to the surface light source with the image displayed thereon, a luminance and a chromaticity of the displayed image should be kept within the limits of respective allowable ranges.
In response to this requirement, some automatic correction methods have been proposed for controlling the luminance and the chromaticity of the displayed image within respective allowable ranges.
One example of an automatic correction method is disclosed by Japanese Patent Laid-Open Publication No. 52958/1992. In the automatic correction method disclosed thereby, a calibration pattern is displayed on a surface light source, and a luminance L of each pixel at the coordinate (x, y) which composes the calibration pattern is measured by a luminance meter placed close to the surface light source. Further luminance data of each pixel (x, y, L) is obtained as an electro-optical transforming characteristic of the surface light source. Then the image data corresponding to the image displayed on the surface light source is corrected by a feedback process according to the electro-optical transforming characteristics. In this conventional method, first the image data is corrected and then the image corresponding to the corrected image data is displayed on the surface light source, so that the variations in the luminance and the chromaticity of the displayed image can be easily controlled and kept within respective allowable ranges.